acoupleofyearsago和couplesofyearsago哪种形式是正确的?如果都正确分别在什么情况下使用,

Question

a couple of years ago和couples of years ago哪种形式是正确的?如果都正确分别在什么情况下使用,

Answer 1

My family and I immigrated into America couples of years ago.
我和家人几年前一起移民到美国的.
It only lasted a couple of years,as far as I know.
据我所知,它仅仅维持了两三年.
网上都有使用的,不过a couple of years ago用得较多,表示“两三年；几年”